Typhoon Sanvu Update #7

Typhoon Sanvu has failed to strengthen over the past 6 hours and continues to move closer towards Iwo To. The center of the storm was last located approximately 570km south southwest of Iwo To, Japan. Maximum sustained winds remain at 120kph gusting to 150kph. TY Sanvu is moving north northwestward at 20kph.

IR Image from NRLMRY

Typhoon Sanvu is now rounding the sub-tropical ridge and should start turning to the northeast tonight. Recent satellite images have shown warming cloud tops and fragmenting of some of the convection. Nevertheless, the center can still be clearly seen on both infra-red and visible satellite images.

MWI from TMI (NRLMRY)

Furthermore, the eyewall of Sanvu remains intact, as seen on the 37Ghz microwave image above. However, a separate 89ghz image (not shown here) shows a partially-closed eyewall, with the SW periphery remaining open. The eye signature is what has kept the storm at typhoon-status.

Favorable conditions is forecast to persist for another 12 to 24 hours. This should allow Sanvu to at least maintain its current strength, if not intensify a little bit more. Soon, it'll start encountering cooler waters and stronger wind shear. But despite those inhibiting factors, we are still forecasting it to be at typhoon-intensity as it approaches Iwo To, Japan by Saturday morning. Then, Sanvu should start to lose strength rapidly and start transitioning into an extra-tropical cyclone during that time frame.

Forecast Track (NOT OFFICIAL!)

We'll have another update tomorrow morning.
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Issued (0830 UTC) 430pm PhT 052412